1. Field
Example embodiments of the present invention may relate to error control codes, and more particularly, to a concatenated decoding method and concatenated decoder where a plurality of error control codes decoder is concatenated.
2. Description of Related Art
Generally, a path transmitting information is referred to as a channel. When information is transmitted via a wired communication, a channel is a transmission line where information is transmitted. When information is transmitted via a wireless communication, a channel is air where an electromagnetic wave including information passes.
A channel may be a process of storing information in a semiconductor memory device and reading stored information from the semiconductor memory device. Also, a channel may be a time passage from when a semiconductor memory device stores information to when stored information is read from the semiconductor memory device, and a channel may be a physical path to store information in a semiconductor memory device and read stored information from the semiconductor memory device.
Information may be corrupted while transmitting information via a channel. Corrupted information includes errors. Much research has been conducted to detect errors from corrupted information, remove detected errors, and restore initial information.
An error control code encoding refers to an operation of adding an additional parity to initial information prior to generating and transmitting a codeword. An error control code decoding refers to an operation of separating an additional parity from received codeword and restoring initial information.
An error rate occurring in a channel may be significant depending on a channel feature. Generally, as an error rate increases, hardware complexity for embodying an error control code encoding and error control code decoding to overcome such errors increases.
A channel with a great error rate may use a concatenated encoder where a plurality of error control code encoders is concatenated. A concatenated decoder is used to restore initial information from information generated by a concatenated encoder.
A concatenated decoder is generally designed in reverse order of a concatenated encoder. For example, when a concatenated encoder includes an encoder A and an encoder B in sequence, a concatenated decoder includes a decoder B and a decoder A in sequence.
A concatenated decoder and concatenated decoding method which improves an error correcting capability is provided in this specification.